AY Honors/Renewable Energy/Answer Key
Renewable energy is any type of energy generation that isn't dependent on a limited resource like fossil fuels. Renewable energy may be used directly, such as solar ovens, geothermal heat pumps, or windmills. Other forms of renewable energy sources generate electricity, such as solar power cells, wind generators, tidal waves and hydroelectric power. Still other forms generate fuels, such as vegetable oils generated from biomass.
Most renewable energy can trace their root to solar energy, perhaps with the exception of geothermal and tidal wave power. For example, wind is caused by the density difference of the air when the sun heats various parts of the earth unevenly. Hydroelectric power can be ultimately traced to the sun too. When the sun evaporates water in the ocean, the vapor forms clouds which later falls on mountains as rain which runs through turbines to generate electrity. The transformation goes from solar energy to potential energy to kinetic energy to electric energy.
Most renewable energy sources have no emissions, with the exception of biomass fuels. Even for biomass, however, the generation of new plantlife consumes the same elements from the atmosphere that it emits when burned.
Iceland is a world leader in renewable energy due to its abundant hydro and geothermal energy sources. Over 99% of the country's electricity is from renewable sources and most of its urban household heating is geothermal. Israel is also notably as much of its household hot water is heated by solar means. These countries' successes are at least partly based on their geographical advantages.
